Fruit treating solution



Patented Dec. 9, 1947 2,432,406

UNITED STATES PATENT OFFICE 2,432,406 FRUIT TREATING SOLUTION Ray D. Gerwe, Clearwater, and Martin A. Slade, Jr., Dunedin, Fla., assignors to Food Machinery Corporation, San Jose, Calif., a corporation of Delaware No Drawing. Application January 13, 1945, Serial No. 572,742

Claims. (01. 99-168) This invention relates to the art of applying a the true cause of which has not yet been deterwaxy protective material dissolved in a volatile mined. With some lots of solvent and cumar, a solvent to fresh whole fruit and the like whereby similar cloudiness appears in the solution when it the material thus deposited on said fruit will reis first made. duce the shrinkage of the fruit and enhance the 6 The finely divided solid matter which is seen as appearance thereof. cloudiness in the solution eventually coagulates While the invention has other applications, it is to the point where it produces flaky particles especially useful in the method of fruit treating large enough to clog the nozzles used in performin which the solution is directed against the fruit ing the Sharma-Sells method. These particles in an atmosphere of fine particles as disclosed in 10 also collect in the delivery drums and spray tanks United states Letters Patent to Sharma, No. 2,- in sufficient quantities to stop up the screens pro- 212.621 and to Sells et al., No. 2,342,063. vided to exclude sediment from the solution with- This method has come into wide use in the drawn from these tanks. Moreover, the fine precitrus and fresh vegetable industries in the United cipitate present in cloudy solution causes the fruit States where it ifknown as spray waxing. The treated therewith to have a much poorer lustre protective material applied in spray waxing varies than is produced by the clear solution.

from soft waxes such as paraffin to harder waxy It is accordingly an object of this invention to materials including certain polymerized resins. provide a fruit treating solution containing a syn- The solvent in which the protective material is thetic resinous product which is suitable for emdissolved for use in spray waxing is a highly volaployment in the Sharma-Sells method aforesaid tile petroleum distillate, which for practical reafor the application of said resinous product to sons preferably lies within a range of an initial fresh whole fruit and the like, and which will be boiling point of 100 F., and an end boiling point free from the objectionable cloudiness and preof 350 F. In the Sharma and Sells spray waxing cipitation of sediment above discussed.

processes an atmosphere of fine particles of the Various theories might be propounded to exsolution is formed by discharging the solution into plain this cloudiness phenomenon in dilute soluthe atmosphere through nozzles which rely entions of cumar and like resins. Extensive extirely upon the hydraulic pressure with which the periments were made to check the most likely of solution is supplied to the nozzles to break the these theories, without, however, being able to latter up into fine particles suitable in size to prove any of them. While the initial cloudiness apply these to the fruit. In the sells process the was thought to result from only partial solubility particles of solution thus formed are rapidly conof the resin in the solvent, it is considered probaveyed in a current of air into contact with the ble that the cumar is never completely disfruit so that there is a relatively small loss of solved, and that a considerable portion of it is solvent by evaporation before the solution dropmerly in a very finely divided state of suspension lets engage the surface of the fruit. in the solvent even when the solution is com- Among the protective materials which have pletely clear.

come into general use in the United States in the Although these experiments did not justify any treatment of fresh fruit and vegetables by spray particular theory for explaining this cloudy phewaxing has been a resin known as cumar, the nomenon. y d l d to e dis overy that t e technical name for which is coumarone-indene condition under study is amenable to the introi resin. This resin is synthetically produced by duction into the solution of a certain few synpolymerization, and when a clear solution of this thetic surface active agents, out of a multitude of is applied to fresh fruit and vegetables in the those which are available.

Sharma-Sells method it gives the fruit a beauti- One of these agents, which is the most effective ful natural lustre, as well as supplying an adequate of all those tried, is known in the trade as Aerodegree of shrinkage control. sol OT. Chemically this is classed as a dioctyl When the solutions of cumar used in this ester of sodium sulfosuccinic acid. The introducprocess are first made up they are ordinarily comtion into a cumar solution of Aerosol OT in pletely clear and the fruit treated thereby exhibits amounts as low as .005% by weight showed defithe unusually bright but natural appearance nite clearing action. In every case .05% to .10%

which this process alone appears capable of proor more of the Aerosol OT efiected complete clearducing. After the solution stands awhile, howing the solution. ever, as is necessary in performing the process A large number of agents are rendered unsuitcommercially, it sometimes takes on a cloudiness 5 able for solving this problem by virtue of the fact that they are incompletely soluble in the tions it was tried upon, it has been deemed adsolvent employed. Others were found to be unvisa 1e, to make sure of the results, to employ treatment, and which also provided immediate therefore, have relatively little effect upon the material after this was deposited on the fruit. the agent, such as 1% to 2% by weight are un- The trade-names, as well as the chemical names, desirable as this causes a noticeable softening of J of these agents, which will be referred as Group the deposited resin. A, are as follows: No change whatever is made necessary in the Group A apparatus customarily employed in performing ros l T O Y ester 0f Sodium the solution of this invention. This apparatus,

sulfosuccinic acid ssentially as used at present commercially, is Aerosol MA Dihexyl ester of S d um disclosed in the patent to Sells at al. abOVe noted. SulfOSllCcinic acid The solvents which it has been found practical At pa SO ta monooleate to use commercially in the Sharma-Sells process f, Duponol 0s Fatty alcohol sulfate include the following:

Seven other synthetic surface active agents 25 Super V. M. & P. Naphtha were discovered which, while not completely sol- 1 11 Lacquer uent c uble in the solvent, contained only a slight standard Solvent Naphtha #14 amount of insoluble material. When any agent sh l R bb s lv t A a any of the agents of Group A for immediate and use Wlth thls mventlon permanent clarification of the solution. These Nevindene seven agents which will be referred to as Group Durez Resin #210 B, are identified by their trade-names and their Durez Resin #570 chemical names, as follows: Piccolyte Group B Nypene Resin A typical formula for the solution of this ingggffigifi. figg g gfi gifi vention includes the following ingredients in the mate 4O proportions noted: Span 20 sorbitan monolaurate Per 2 3 8 Span 40 Sorbitan monopalmitate Cumar Span 60 Sorbitan monostearate Spermacetl q Tergitol Penetrant 4 Sodium salt of higher seccottonseerirol 66 ondary alkyl sulfate 4 Aerosol O 93'90 'I'ergitol Penetrant 7 Sodium salt of higher sec- Petroleum dlstl late Solvent lda y a yl sulfate In making up the solution for practicing the Efiorts to classify agents which were found to invention commercially it has been found prefclarify the solutions under discussion so as to disa the first Ftep, 1 prepare concfmtrate tinguish these, in terms of some common chap containing a ll the ingredients of the solution exacteristic, from those agents which were not suitcept for omllitmg most of T able for this purpose, were in the main unsucstep of formmg the solutlon 1s accomphshed cessful. It was noticed, however, that in the drums, of the solvent by ietmducing swtable case of the Aerosols, those containing paraifin f concentrate Into the drums and hydrocarbon groups of less than six carbon atoms, mlxmg thls Wlth the solvent theremas for instance, amyl, butyl, and iso-propyl are The claim? are:

not soluble in the solvent employed and have no A solutlon applym? protecfilve mate1:1a'1 clearing action. On the other hand, those agents to fresh fruit Whlch Fompr 159s coumaronem with hydrocarbon groups having six or more cardene 2 dlssolved hlghly Volatlle F bon atoms, as, for instance, hexyl and octyl, are leum distillate solvent and an ester of sodium satjsfactory sulfosuccimc acid with a hydrocarbon group hav- The synthetic surface active agents mentioned ing at least Six carbon in Groups A and B as having been found suitable A solution for applying protective material for use in this invention, belong to one or the to fresh fruit Whlch Comprises a Sy th c es n other of two chemical classes, anionic and nondissolved in a highly Volatile petroleum distillate of sulfosuccinic acid, fatty alcohol sulfates, modiwith a hydrocarbon group having at least six fied alkyl aryl sulfonates, and sodium salts of a carbon atoms.

higher secondary alkyl sulfate. The agents men- 3. A solution for applying protective material tioned which are embraced in the non-ionic class to fresh fruit which comprises a synth tic resin include sorbitan monooleate, sorbitan monodissolved in a highly volatile petroleum distillaurate, sorbitan monopalmitate, and sorbitan late solvent and an agent selected from a group monostearate. of anionic surface active agents consisting of While as little as .05% by weight of the Aerosol esters of sodium sulfosuccinic acid with a hydro- OT effected a complete clearing of all the solucarbon group having at least six carbon atoms,

fatty alcohol sulfate, modified alkyl aryl sulcinic acid with a hydrocarbon group having at least six carbon atoms, fatty alcohol sulfate, modifled alkyl aryl sulfonate, and a sodium salt of a higher secondary alkyl sulfate.

fonate, and a sodium salt of a higher secondary alkyl sulfate.

4. A solution for applying protective material hich comprises a synthetic resin troleum distillate f approximate solvent having a boiling range 0 1y 100 F. to

AY D. GERWE. MARTIN A. SLADE, JR.

REFERENCES CITED The following references are of record in the 10 file of this patent:

UNITED STATES PATENTS elected from a grou consisting of: esters acid with a hydrocarbon x carbon atoms, fatty alsodium salt of a higher secon 5. A solution for applying to fresh fruit which co dissolved in a petroleum a boiling range F., and at least .0 lected from a gro 5% by weight 0 Name Date Sharma July 21, 1942 Kalmar Dec. 17, 1946 Bennett Dec. 19, 1939 Tisdale Sept. 3, 1940 Sharma Aug, 27, 1949 Wehrli July 13, 1943 Redlinger Nov. 9, 1943 agents consisting of: esters of sodium sulfosucrwt 

